February 5, 2023

The Mammoth Senator Tunnel

In the early prospecting days of the 19th century, the Senator and other adjacent mines were thought to be a bonanza of gold ore. They were worked down until they reached water and work was given up. However, in early 1905 a plan was announced that would completely revive the Mt. Union section of the Hassayampa mining district.

According to the Weekly Journal-Miner, many thought that Phelps Dodge and Company “had practically withdrawn from this section,” but the opposite was true. The Commercial Mining Co, a subsidiary of Phelps Dodge, had been “quietly buying up mining properties in the vicinity of the Senator mine,” the Journal-Miner revealed. They intended to reach these veins from underneath with the construction of a “humongous” tunnel.

The plan was to “drive the [tunnel] clear through [Senator] mountain and cut a number of well-known ledges, which exist there at great depth,” the paper explained. “The project of a tunnel through the Senator mountain is by no means a new one, as the question has been agitated from time to time for years and has been pronounced by mining men who have examined it as not only feasible, but practical with a reasonable prospect of encountering large bodies of ore.” (“Senator Mountain” is west and slightly north of Mt. Union.)

The Arizona Silver Belt newspaper added that after the Senator vein was reached, work would continue next to the Ten Spot claim. Additionally, the company hoped to place “a concentrating plant at the mouth of the tunnel, from which latter ore cars will run out so as to dump the ore right into the bins of the concentrating plant,” the paper stated.

The massive project started in February, 1905 and it was expected that eventually 500 men would be employed there.

Most of the supply for the project would be procured from nearby Prescott—about 12 miles away. The Weekly Journal-Miner was excited at the prospect: “Not only would the inauguration of this enterprise give employment to a large number of men, but its consummation would prove the means of affording facilities for the economical working of a large number of properties in that section, which make a good surface showing.” Still, when the project was first announced, “it was received with somewhat of a skeptical mind.”

Major AJ Pickerell was named manager of the project and he explained to the Prescott paper that it would be “a continuation of the old Senator tunnel [and] driven at least 600 feet further east” to meet with the Ten Spot mine several hundred feet [below] the surface. Practically an underground distance of 2000 feet will be opened, and…this tunnel will crosscut several other leads known to exist…”

Max Alwens, who had a Mercantile in Maxton (which served the Senator mine,) told the Journal-Miner that the water flume from the Hassayampa was being repaired “and the dwellings and other buildings were put in repair.” 

In early March, the Sam Hill hardware store manufactured a 2500 foot, six-inch pipe to pump fresh air into the latest work area. The following week an equally long iron pipe for compressed air was installed. Fourteen men were actively constructing the necessary infrastructure.

When this preparatory work was completed, the expansion of the tunnel continued in earnest. By mid-April it was reported by the Arizona Daily Star that “the air drills have started up in the Senator tunnel…[and] three 8-hour shifts of men are steadily at work.” 

The Bisbee Daily Review explained: “The Senator tunnel was started…for the purpose of striking the ore veins that crop out on the surface, at a great depth. A better natural tunnel site could not be found in the county than the Senator mountain.” Over several years the Senator mine produced “many tons of rich ore” and it was hoped “there [would] be ore to keep milling for years to come.”

Another important function of the tunnel was to drain the water in the shafts above. It was known for years that rich gold ore existed under this water and now it could be extracted.

In early 1906 “the north drift from this great tunnel, on the Ten Spot vein, exposed a ledge eight foot wide [vein] of fine concentrating ore, while the south drift on the same ledge has exposed two feet of almost solid galena ore,” the Arizona Daily Star reported. “This remarkable showing will stimulate deep mining throughout the district, and the coming season will see hundreds of men at work on the various groups mines,” it predicted.

By March 1906 the tunnel had grown to 2700 feet. “The shaft on the Ten Spot vein is being sunk to connect with the tunnel,” the Journal-Miner related. Then “work will be resumed on the main tunnel and continued until the Treadwell, Cashier, Snoozer and other parallel veins are encountered.”

Story Behind the Place Name: The Bradshaws

The story of William and Isaac Bradshaw’s adventures in Yavapai County and the history of the ghost town Bradshaw City.

When the Treadwell vein was reached in June, the Journal-Miner deemed it “richer than the initial discovery…” Work on clearing out the ore continued and there was even a survey completed to run a railroad spur to the tunnel entrance in 1907. 

In August 1907 the Snoozer vein was reached at a depth around 1000 feet. “The water in the vein will drain through the tunnel, which will facilitate the work sinking the shaft,” the Journal-Miner described. The Snoozer vein also became larger at depth. “The vein is now 150 feet in depth, and the pay streak…is holding out well and increasing in copper and gold values as depth is gained.” 

Eventually three separate ledges were discovered by the Snoozer extension. By March of 1908, the tunnel had reached a distance of 3000 feet, and was “being pushed ahead to open other promising ledges,” the paper divulged.

It was observed that all the various veins became even richer at depth. However the gold near the surface of the mountain was giving way to an even richer deposit of copper.

Work on the Snoozer paused for several months until late in 1911. In November of that year, “expert examination of underground conditions,” was made, according to the paper. A drift was constructed to de-water the tunnel before work started toward the Cash mine.

The Cash mine was only 200 feet from the Senator tunnel and its owners reached an agreement with the Commercial Mining company to make a crosscut at the 1800 foot distance of the tunnel. According to the Mohave County Miner, just like all the other veins, they “encountered a small streak of ore which they followed and…the streak widened gradually [to the] proportions of a bonanza.”

By 1913, the Bisbee Daily Review reported that the tunnel was “more than three-fifths of a mile in length, and a drift was run to the Cashier vein, which [was] intersected by the tunnel some 3000 feet from the mouth.”

In September 1915 the tunnel had reached a length of 4500 feet; “from which a drift [was] run to tap the main ore shoot of the [burgeoning] Snoozer,” the Journal-Miner revealed. By July 1916 the tunnel was 4800 feet long and “a vein of a 12% copper ore has been exposed,” the paper exclaimed. 

In the early surface mining days of the Senator and adjacent mines, they were gold mines. But the Senator tunnel revealed that the gold was merely a cap for an even richer copper deposit underneath. “It is now believed that the Senator mountain is a basin of copper, and its capping [of gold] has been a delusion from the day the mine [opened]. The situation is evoking very much surprise,” the Journal-Miner noted. Three years later the tunnel tapped-out and the post office closed in 1918. 

However, as soon as the Senator tunnel proved successful back in 1906, another tunnel project was begun underneath the nearby Storm Cloud mine group. It too, proved highly successful.

In succeeding years several more tunnels were bored into the Bradshaw mountains; some between two and three miles long. Indeed, the Senator tunnel’s success marked the beginning of a new, successful, and final chapter in the major mining of the Bradshaw mountains. 


Now Available!
The New Book by Drew Desmond and Brad Courtney:
"True Tales of Prescott" 

Follow the blog in one of the following social media to be sure you get the latest article!

Want more Prescott history? Join the "Celebrating Historic Prescott" group.
(Daily pics and featured articles.)
Drew Desmond is on Facebook (For the latest article and posts about Drew's writing.)

Follow the Prescott AZ History Blog on Twitter @PrescottAZHist
(Daily pic featured at 7 am and featured articles.)

Prescott AZ History is on Pinterest
(For the latest article.)

Follow PrescottAZHistory on Instagram


Weekly Journal-Miner; 1/18/1905, Pg. 8, Cols. 1-2.

Arizona SilverBelt; 1/26/1905, Pg. 3, Col. 2.

Weekly Journal-Miner; 2/1/1905, Pg. 1, Cols. 3-4

Weekly Journal-Miner; 2/22/1905, Pg. 7_c3

Weekly Journal-Miner; 3/8/1905, Pg. 8_c1

Weekly Journal-Miner; 3/15/1905, Pg. 8_c4.

Arizona Daily Star; 4/13/1905, Pg. 8_c4.

Bisbee Daily Review; 8/17/1905, Pg. 2_c3.

Arizona Daily Star; 1/19/1906, Pg. 3_c2-3.

Weekly Journal-Miner; 3/7/1906, Pg. 4_c5-6.

Weekly Journal-Miner; 6/20/1906, Pg. 7_c3.

Weekly Journal-Miner; 5/6/1907, Pg. 7_c3.

Weekly Journal-Miner; 8/7/1907, Pg. 8_c2.

Weekly Journal-Miner; 10/9/1907, Pg. 6_c6.

Weekly Journal-Miner; 3/4/1908, Pg. 4_c6.

Weekly Journal-Miner; 11/8/1911, Pg. 2_c3.

Mohave County Miner; 6/1/1912, Pg. 3_c3.

Bisbee Daily Review; 1/5/1913, Pg. 7_c3.

Weekly Journal-Miner; 9/15/1915, Pg. 4_2.

Weekly Journal-Miner; 6/28/1916, Pg. 2_c4.

No comments:

Post a Comment